Refrigerating apparatus



APril 7, 1931- H. K. SELLICK ET AL REFRIGERATING APPARATUS Filed May 13,1929 JS & mzfaizz AT'TORNEY Patented Apr. 7, 1931 UNITED STATES PATENTOFFICE HAROLD K. SELLICK AND MILTON KALISCHER, OF MANSFIELD, OHIO,ASSIGNORS TO WESTINGHOUSE ELECTRIC do MANUFACTURING COMPANY, ACORPORATION 01' PENNSYLVANIA BEFBIGERATING APPARATUS Application filedMay 13,

This invention relates to refrigerating apparatus and more particularlyto the evaporators or cooling coils embodied 1n such apparatus. It is anobject of the invention to materially increase the effective coolingsurface of the evaporator without increasing the length of the coilsutilized to conduct the refrigerant fluid.

Another object is to eliminate the brine tank, sometimes used as acold-storing element, and to substitute therefor a mass of metal inwhich the refrigerant coils are embedded.

A still further object is to provide-an evaporator comprisingrefrigerant coils embedded in a mass of metal, the metal serving toincrease the effective cooling surface of the evaporator to protect thecoils against injury and corrosion and to provide a freezin chamber forthe reception of ice-trays.

ore specifically, the invention has for its object to provide a meansfor protecting the cooling coils whereby they may be embedded in a metalcastmg at a relatively high temperature. without marring or destroyingthe coil.

Other objects and advantages of the 1nvention will be apparent from thefollowing description and accompanying drawings,

wherein, a

Figure 1 is a perspective view of the refrigerant coil utilized in thisinvention,

Fig. 2 is a pers ective view of a complete evaporator embo ying theinvention,

Fig. 3 is a vertical sectional view through the evaporator, showing theembedded 0011s, and

Fig. 4-. is an enlarged cross-sectional view of the tubing utilized inbuilding the evaporator, and taken on line IV"IV of Fig. 1.

It has heretofore been proposed to employ quantities or masses of metaladjacent to the evaporator coils in order to dispense w1th the use of abrine tank and to increase the radiating surface of the evaporator. Thegeneral ractice has been to wrap the colls around t e outer surfaces ofa metal block, the block itself being provided with a hollow portion orrecess to receive an ice tray.

1829. Serial No. 382,776.

coils to dissolve in the aluminum when the latter is in its moltenstate. This is true even though the melting point of aluminum is 658 andthat of copper is 1083 C.

Copper tubing is particularly desirable for use as the refrigerant coilbecause of its flexibility whereby it may readily'be formed on a mandreland also because it is chemically inert to the refrigerants used inhousehold niachines, for example, sulphur dioxide, ethyl chloride,methyl chloride and isobutane. Aluminum is also preferred as theencasing metal because of its relatively low specific weight andrelatively high specific.

heat, as compared with other metals, and in addition, it is not corrodedby exposure to the atmosphere.

This invention provides an evaporator comprising a copper coil embeddedin aluminum, the coil being rotected from the destructive action of t ehot aluminum by a coating of a metal having a melting point higher thanthat of either copper or aluminum. We find that, bfv plating the coppertubing with a metal 0 high melting point, for example, nickel, chromium,cobalt, or an alloy of one of them that the tubing is not affected bythe molten aluminum during the casting process.

Referring to the drawings, wherein is shown a preferred embodiment ofthe invention, 10 designates a tube, preferably of copper, which has itsouter surface plated, as indicated at 11, with a metal which has ahigher melting point than aluminum or copper and is chemically inertwith respect to these metals. We have found that nickel may besuccessfully utilized for this purpose.

The plated tubing is wound on a suitable mandrel (not shown) to thedesired shage, and the coil is held rigidly in position y suitableclamping strips 12, arranged in pairs at suitable intervals around thecoil; screws 13 are located between the turns of the coil to retain theindividual pairs of clamping strips rigidly in place. The ends of thecoil project vertically upward, as indicated at 14: and 15, to serve asa' means for connecting the evaporator to the refrigerant circulatorysystem.

After the coil has been formed and braced, it is inserted in a suitablemold (not shown) and the molten aluminum is poured about it. The moldmay be of such a shape as to provide heat-dissipating fins 16 on thevertical surfaces of the evaporator and also to provide a recess orfreezing compartment 17 having molded ledges 18 on its opposite verticalwalls for receiving ice trays.

The open end of the evaporator may be provided with a door 19 to furtherincrease the effectiveness of the freezing compartment.

While we have described a cast evaporator having a coil of copperembedded in an aluminum casting, it will be apparent that our inventionmay be applied to any castmetal evaporator in which there is a tendencyfor the metals of the coil and the casting tc absorb each other whenheated, or in which it is desired to form the coil and the casting ofthe same metal, it being merely necessary in any case, to protect thetube b a coating of a metal having a higher melting P0111; than themetal or metals comprising the elements of the evaporator and which is,ar. the same time, chemically inert to these metals.

Although We have shown and described specific embodiment of ourinvention, it Will be apparent that other forms might be adopted, allcoming within the scope of the appended claims.

We claim as our invention:

1. A cooling unit for a mechanical refrigerating system comprising aplated copper coil embedded in an aluminum casting.

2. A cooling unit for a mechanical refrig crating apparatus comprising acoiled copper tube having a plated outer surface and an aluminum massencasing said coil.

3. A cooling unit for a mechanical refrigerating apparatus comprising arefrigerant conveying element, a metallic coating on the outer surfacesof said element and a metallic mass encasing the element, said metalliccoating being formed of a metal having a higher melting point thaneither of the metals forming the element and the encasing mass.

4;. A coolingunit for refrigerating apparatus comprising a plated copperrefrigerant-conveying element embedded in an aluminum casting.

5. A cooling unit for refrigerating appa- HAROLD K. SELLICK. MILTONKALISOHER.

